Self-propelled model submarine



March 1l, 1958 F. G. PRESNELL SELF-PROPELLED MODEL SUBMARINE Filed May11, 195e L V., WQ QN E m. M M WNH MNHN m m. m Huwmhw Mmmmwml. m R rnmwmmwu. N P .u 1 G. K wmv K K Q wk M. um M f Y B SELF-PRUPELLED MODELSUBMARINE Frank G. Presneil, Hollywood, Calif.

Application May 11, 1956, Serial No. 584,287

7 Claims. (Cl. 4694) This invention relates to toys and particularly toa new and improved self-propelled model submarine.

Generally, self-propelled model submarines have positive buoyancy andinclined diving planes which cause submergence by exerting a downwardforce when the model is propelled forwardly through water. Resurfacingoccurs after the dynamic downward force is reduced, in consequence ofloss of speed due to exhaustion of motive power, to a point wherebuoyancy predominates.

The diving planes may be arranged to effect either evenkeel of bow-downsubmergence. Diving planes giving even-keel submergence exert a backwardforce as the model rises to resurface, thus slowing the models forwardprogress during resurfacing, or even causing the model to move backwardwhile resurfacing. Generally, planes arranged to give even-keelsubmergence must be un realistically large in order to be effective.While planes arranged to give bow-down submergence tend to avoid thesedisadvantages, suchplanes are difficult both to proportion and adjust,as slight variations in the size or setting tend to result in the modelseither refusing to submerge, or diving too steeply.

Propulsion for model submarines can be provided inexpensively by the useof rubber bands driving an ungeared screw propeller. However, rubberbands are tedious to wind, and with such propulsion it is diicult tocombine realistic appearance and good performance, since a propeller ofrealistic size is incapable of preventing excessively rapid unwinding ofthe bands if the latter are sufiiciently heavy to store much power,while if the bands are light enough to permit satisfactory duration ofpropulsion with a propeller of realistic size, little power can bestored, and the models speed will be low. Further, a model submarine haslittle lateral stability, and a single propeller tends to cause themodel to heel excessively. These disadvantages can be avoided by the useof geared twin propellers which, however, add to complication and cost.

A primary object of this invention is, accordingly, the provision of anew and improved model submarine of simple, inexpensive constructionwhich is propelled submerged at a satisfactory speed for a relativelyextended period of time, and Whose trim is controlled to afford themodel a slight, definite dive angle when submerging and aslight,definite rise angle when surfacing.

Another object is the provision of an improved propulsion device formodel submarines, which device is simple in construction and capable ofstoring a relatively large amount of power that is expended at acontrolled rate to give relatively prolonged propulsion at satisfactoryspeed.

Yet another object is the provision of an improved propulsion device asin the foregoing wherein the rate of utilization of the power stored bythe device may be simply varied.

A further object is the provision of a model self-propelled submarine ofthe class described which, during submergence thereof, is trimmed to arealistic dive angle, and` Patent 2 which trim is automatically changed,in response to the exhaustion of power in the propulsion system, to givethe model a rise angle and thereby assure realistic surfacing thereof ina forward direction.

A still further object is the provision of a self-propelled modelsubmarine of the class described which is so constructed as to insurethe removal of unwanted air from the propulsion device and from theinterior of the model.

Another further object is the provision of a model submarine having auid jet propulsion system embodying a check valve movable by gravity inresponse to loss of pressure in the propulsion system to shift thecenter of gravity of the model and thereby change the trim of thelatter.

Yet a further object is the provision of a novel fluid pump for use witha jet propelled model submarine of the class described.

These and other objects are accomplished in the illustrative embodimentof the invention by the provision of a submarine-shaped hull enclosingan elastic propulsion tube adapted to be inflated with water. Duringoperation of the model, the water in the propulsion tube is expelled, bycontraction of the tube, through an after nozzle opening for propellingthe model forwardly. A ballast member, which, in the illustrativeembodiment of the invention, also functions as a valve to close aforward hull opening through which the propulsion tube is filled, isretained, by the pressure of water in the tube, in a forward position ofsealing engagement with said opening whereby the model is made slightlybow heavy so that it assumes a slight dive angle for submergence. Uponcon traction of the propulsion tube to substantially its normalcondition, the ballast member is released for movement by gravity to arearward position whereby the model is made slightly stern heavy so thatit will assume a slight rise angle for surfacing in a forward directionunder the action of the buoyant force therein.

The pump for filling the propulsion tube is of novel design including acontainer for water, and a reciprocable member engageable directly withthe hull of the model about said forward opening and adapted forreciprocation, by movement of the hull, to pump water from the containerto the tube interior.

The invention possesses various other novel features, such as means forassuring proper and complete inflation of the propulsion tube, completeremoval of air from the interior of the hull, and realistic otation ofthe model when surfaced, which will become readily apparent as theensuing description proceeds, reference being had therein to theattached drawings wherein:

Fig. 1 is a section taken longitudinally through the present modelsubmarine showing the latter during diving thereof;

Fig. 2 is a reduced section taken along line 2-2 of Pig. 1;

Fig. 3 is a reduced section taken along line 3-3 of Fig. l;

Fig. 4 is a reduced section taken along line 4--4 of Fig. l;

Fig. 5 is a section, on reduced scale, similar to Fig. 1 showing-thepresent model during surfacing thereof;

Fig. 6 is a section through the pump for filling the propulsion tube ofthe present model; and

Fig. 7 is a section taken along line 7-7 of Fig. 6.

The model submarine illustrated in these drawings. comprises a hollowhull 10 preferably constructed as a plurality of rigidly joined, moldedplastic sections, as

shown. The model includes horizontal and `vertical stabilizing planes 12and 14, respectively, disposed in axial planes of the hull, and a hollowconning tower 16. Hull 10 and conning tower 16 have ports 18 and 20 toadmit i water to the interior thereof, and the planes v12 and `14 may'aseaooi have openings 22 formed therein to receive weighted slugsfor'longitudinal and lateralbalancing of the model. VYThe conning tower16 is secured to the upper portion of hull lib, as shown.

:The -forward and after ends oflhull 1'0 areiformed with axial Vopenings24 Vand 26, respectively, the former deiining an inlet port for fillingof the models propulsion system, generally indicated at 28, as willshortly'be more fully described, and the latter lhas the reduced afterend ofa-sleeve 30 fixed therein.

Sleeve 3i) has abore 32 extending into its forward end, which .bore iscontinued in aireduced bore 34'having its after end continued .in astill further reduced bore Yforming a nozzle 36. The forward endof'sleeve Sil-is formed Withfa bead 38.

Secured aboutits periphery'to the interior wall Vof the one piece bowsection of the hull as by suitable -adhesive, is a rearwardly tapered,cone-shaped wall 40lhaving a central, rearwardly, projecting stud 42.Stud 42 has a bead 44, and is formed with a central bore 46 whichiscontinued at its forwardend in a reduced bore V48 opening to theforward sideof wall 40.

A-rod 50 has its opposite ends received in the-enlarged bores 32 and 46in sleeve 30 and stud 42 and 1s .grooved at opposite ends, as shown at52. Indicated at 54 is Aa `tube of elastic material, such as rubber,having its opposite ends stretched over the beaded ends 38 and 44 of thesleeve 30 :and stud 42, wire bands 38a and l44a being used -to assure asecure it. The grooves 52 in rod Sil-serve to permit the flow of waterthrough the central-opening i8 in wall 40 into tube 54 and from the tubeinto :bore 34 and nozzle 36.

Disposed .in the forward compartment 37 of .the hull, defined by theforward wall of the hull and -wall fill, is a steel ball 56 which isadapted to occupy forward position in said compartment, shown in Fig. l,wherein it-seals the opening 24, and a rearward position, showninFig. 5.It will be seen that if the pressure in said compartment-is greater thanexternal pressure when opening 24 is scaled by ball 56, the latter willbefretained in said forward `position even though the hull occupies agenerally horizontal position. If, however, the pressure in thecompartment be equal to or :less than Vsaid external pressure with thehull in the position of Fig. l, the -ball will roll along the downwardlyinclined inner surface or vfloor of the compartment 37 to said rearwardposition lof Fig. 5`

Formed on the yupper portion of -t'ne inner wall of lhull 10 is alongitudinal rib 58 and pieces-66 and-62 of .buoyant material aresecured in the upper portion ofthe hull interior at the forwardand-'after ends thereof. The volume and vertical positioning lof this'buoyant material in the hull are such as to give vthe model positivek:buoyancy 'and a positive metacentric height when lthe entire hull,Fincluding compartment 37 and tube 54, are filled with water. Thelongitudinal disposition of the buoyant material is such that with theentire hull lled with water, and with ball 56 moved to its forwardposition, the center of gravity of the model is slightly forward of itscenter' of buoyancy to give the model 'a slight dive angle, as Vshown inFig. 1, and with the ball moved to its rearward position, the center ofgravity is slightly aft of the center yof buoyancy to give the model aslight rise angle, as shown in Fig. 5.

Illustrated in Figs. 6. and 7 is a pump which may be employed forfilling andexpanding the elastic propulsion tube 54 of the presentmodel. This pump comprises an open top container 64 adapted to be filledwith water, as shown. Centrally fixed to the bottom wall of thecontainer is a hollow, upstanding, cylindrical barrel 66 the centralpassage 68 in which opens through the upper end thereof. The lower endVof the passage is` continued in a reduced, right anglepassage-7tl-opening through the wall of barrel 66 adjacent the bottomwall of the container so that water may ow from the container into thebarrel. The. wall of passage 70, at its juncture with passage 63,

l is beveled to form a valve seat 72 for a ball check valve 74.

Slidably telescoping over barrel 66 is an outer barrel 76 in the wall ofwhich is fixed a headed sleeve 78. Sleeve 78 has a passage 80 extendingtherethrough and projects into an elongated slot 82 in the inner barrel66 to limit the telescoping movement of the outer barrel 76. The louterend of passage is beveled to form a valve seat in sealing engagementwith which is retained, by an arcuate leaf spring 86 extending part wayaround the outer barrel, a ball check valve 8S. This check valvefunctions as a relief valve, as will presently be described. The upperend wall of the outer barrel is formed with a central opening 90taperedto conform substantially to the tapered bow of hull 10. A coilcompression spring 94 bears at opposite ends against the bottom of theinner barrel and the upper end of the outer barrel so as to normallyretain the Aouter barrel at its upper limit of travel von the innerbarrel.

In use of fthe invention, the'hull itl is filled with water throughitsVafter ports 18, preferably by submerging the hull bow `down in avertical position, and container 64 of the pump is-va'lso filled withwater, as shown. The bow of the hull isthen placed in the opening 90 inthe upper end of the outer"barreli76 ofthe pump, as shown in phantomlines inf-Fig. 6.

The hullisreciprocated with its bow so engaged with the outer pumpbarrel, whereupon ball check valve 74 will alternately open and close insuch a manner that water will be pumped from the container 64, throughthe forward hull port 24, into the forward compartment 37 of the hulland thence into the elastic tube 54, the airin the forward compartmentand tube 54 being thereby expelled through the now uppermost nozzleopening 36. The conical shape of wall 40 prevents the entrapment of anyair in the forward compartment 37 of the hull during the pumpingoperation even though the hull is not held trulyI vertical. Air inthecompartment would, of course, upset the balance of the model whenafloat.

.After 4all of the air has been expelled from 'the compartment and tubethrough the nozzle 36, as indicated by water issuing therefrom, thelatter is sealed .by the operators linger. Continued reciprocation ofthe hull and outer pump barrel to pump water Iin the propulsion tubewill cause the latter 'to expand with resultant outward flow, throughthe hull openings 18, of the water in the hull which is displaced by theexpanding tube. The tension of the leaf spring 36 on the pump is madesuch that upon the tube expanding into engagement with the interior wallof the hull, as shown 'in Figs. 2 and l, the rise in pressure will causethe ball check valve 88 to unseat and permit the escape of water fromthe pump interior, thus indicating that the propulsion tube is fullyexpanded.

It will ybe observed from Fig. 2 that a pair of small longitudinalpassageways 96 are formed between the rib 58 'and expanded tube '65vthrough which water, displaced by the expanding tube, may flow from theforward part of vthe hull to the rearrof the hull and thence out throughthe hull ports 1:3. Entrapment of water in the forward portion of thehull, with `resultant incomplete expansion of the tube, is ythusavoided. Rod 50 extending through the tube 54 prevents kinking yof thelatter during expansion thereof, Vas would be p'rone to occur in theabsence of such rod.

After -the propulsion tube has been completely expanded, the model .isremoved from the pump whereupon the ball check valve 56 in the bow ofthe hull will be retained in -its forward position, wherein it closesand seals the hull-port 24, under the pressure of the water in theforwardk compartment due to the expanded condition of the elasticpropulsion tube.

The model is now placed in water and released to un- `cover the 'nozzle36, and contraction of the expanded elastic vpropulsion tube 54 causesthe issuance of a jet of water from the nozzle to propel the modelforwardly.

Because of the previously described disposition of the buoyant materialin the upper interior of the hull, rather than in the conning tower, thehull will initially oat with its conning tower extending a substantialdistance above the water surface. Owing to the retention of ball 56 inits forward position, the model will assume a slight dive angle, as washeretofore discussed. The openings 20 through the conning tower wallpermit the conning tower to fill with water when the model submerges,and as the tube S4 contracts, water is drawn into the hull through theafter hull ports 18 so that the buoyancy of the model and its angle ofdive remain substantially unchanged.

The model will continue to dive until the propulsion tube 54 hascontracted to such an extent that the pressure of the water in the tubeand the forward compartment 37 approximates the external water pressureat the depth of the model. Ball 56 will then be released to roll to its|after position, shown in Fig. 5, along the forward, inclined inner hullsurfa-ce, as previously described.

Rearward movement of the ball shifts the center of gravity of the hull,as previously explained, to give the model a slight rise angle, and thepositive buoyancy of the model causes it to rise. Owing to the slightrise angle, the stern planes 14 produce a planing action having laforwardly directed force component during upward movement of the buoyantmodel through the water so that it will tend to move in a forwarddirection while resurfacing. The ports 20 in the conning tower permitthe drainage of water therefrom upon surfacing of the model so that thelatter will realisticly completely resurface with its conning towerabove the water surface.

Since the stern planes 14 are disposed in `a neutral position and themodel is caused to assume a dive angle, during submergence, by a forwardpositioning of its center of gravity rather than -by the action of sternplanes, the dive angle is substantially unaffected by the speed of themodel and delicate adjustment of the planes to achieve a desired diveangle is not necessary. The use of a jet propulsion system avoidsheeling, as occurs in models employing a single screw, rotary propulsionmechanism, and enables the submerged speed of the model to be easilyadusted by the proper choice of nozzle size.

It will be apparent that there has been described a model,self-propelled submarine which is fully capable of attaining the objectsand advantages preliminarily set forth. While a present preferredembodiment of the invention has been described, it is illustrative innature only, many modifications in the design and 'arrangement of partsthereof being possible within the scope of the following claims.

I claim:

1. A toy submarine comprising: an elongated buoyant hull having forwardand after ends, a Huid pressure system in the hull comprising anexpandableelastic tube; there being an inlet opening through the forwardend of the hull communicating with :said tube for lling said tube withwater under pressure to expand the tube and a discharge opening throughwhich water may be expelled by contraction of the tube; a ball checkvalve adapted to be retained in a forward position sealing said firstopening by pressure of the Water in said system; the center of gravityof the hull being forward of its center of buoyancy when the ball is inits forward position whereby the hull will assume 'a slight down anglewhen normally supported in water; a floor surface for said ball checkvalve adjacent said inlet opening which slopes downwardly toward saidafter end when the hull is inclined at said down angle; said ball beingreleased to roll along said surface to a second position wherein thecenter of gravity of the hull is rearwardly of its center of buoyancy inresponse to loss of pressure in said system whereby to cause said hullt-o assume an up angle.

2. The subject matter of claim 1 wherein said second opening denes anozzle through which water in Sad system is expelled in the form of ajet by contraction of the tube to propel the model.

3. A toy submarine comprising: an elongated, hollow, buoyant hull havingforward and after ends; said hull having an opening in its forward end;a conduit member rigid in the after end of the hull defining arearwardly directed nozzle opening through the after end of the hull; atransverse Wall within and adjacent the forward end of the hull andsealed about its edge to the inner wall of the hull whereby to formforward and after compartments in the hull, said wall having a centralopening therethrough; a ball in the forward compartment adapted to closesaid forward opening; an elastic, open ended tube in said aftercompartment sealingly secured at opposite ends to said wall and conduitmember and having its interior in communication with said openings inthe wall and conduit member, said forward opening being adapted to becommunicated with a source of water under pressure to fill and expandsaid tube; said nozzle opening being adapted to have the water in thetube expelled therethrough for propelling the hull forwardly bycontraction of the tube when said ball is retained in a position ofsealing engagement with said forward opening by the pressure of water inthe tube and forward compartment; and said hull having openingstherethrough below the normal surfaced water line thereof communieatingto the interior of the hull about said tube.

4. The subject matter of claim 3 wherein in said sealing position of theball, the weight of the latter causes the center of gravity of the hullto be slightly forward of its center of buoyancy to give the hull a downangle when normally supported in water; and the lower portion of theinner wall of said forward compartment sloping rearwardly and downwardlyaway from said forward opening toward said wall when the hull is freelysupported in water whereby the ball when released is adapted to roll toa rearward position against said wall; the center of gravity of the hullin the latter position of the ball being slightly aft of its center ofgravity.

5. The subject matter of claim 3 wherein said wall is cone-shaped withits apex projecting rearwardly of the hull whereby to assure completeremoval of air from the forward compartment when the tube is lled withthe hull held in a generally vertical, bow down position.

6. The subject matter of claim 3 including a rigid rod within the tubeand secured at its opposite ends in said wall and nozzle openings; theends of the rod being slotted to provide said communication between thetube interior and said openings.

7. A toy submarine comprising: an elongated, hollow hull having a nozzleopening in one end; an elastic tube within and xed at opposite ends tothe hull, the interior of the tube communicating with said opening andbeing fllable with water to cause expansion of the tube, subsequentcontraction of the tube causing a jet of water to issue through saidnozzle opening for propelling the hull through water; and a rigid rodextending longitudinally through the tube and attached at opposite endsto the hull to prevent kinldng of the tube during expansion thereof.

References Cited in the le of this patent UNITED STATES PATENTS1,205,759 Lewis Nov. 2l, 1916 1,262,051 Humphrey Apr. 9, 1918 1,306,284Seidl June 10, 1919 1,903,805 Buckley Apr. 18, 1933 2,194,564 MiddlerMar. 26, 1940 2,549,428 Costea Apr. 17, 1951 2,661,571 Ramsay Dec. 8,1953 FOREIGN PATENTS 657,263 France Jan. 12, 1929 955,455 France June27, 1949

